The long-term goals of this research are to understand the mechanisms that regulate human alcohol dehydrogenase (ADH) gene expression, and the physiological and pathological consequences of alterations in ADH expression. We hypothesize that differences in the expression of the ADH genes affect the metabolism of alcohol, the risk for alcoholism and the physiological and pathological consequences of alcohol consumption. To begin testing this hypothesis we will identify the regions that control ADH expression, identify polymorphisms in these regions, and then analyze whether these polymorphisms affect gene expression.We will identify cis-acting elements important in the regulation of the human ADH genes, with primary focus on the class I genes and ADH7. These have different patterns of expression, and produce enzymes that influence important metabolic processes including metabolism of ethanol and retinol. Cis-acting elements will be identified by a combination of functional studies (transfections) and protein-binding analyses (DNaseI footprinting and gel retardation). We will identify transcription factors that bind to these sequences. The ADH genes are clustered on chromosome 4, and we hypothesize that distant flanking sequences are important in regulating this group of genes. We will test this hypothesis by studying more distant sequences, extending at least 10 kb from the coding regions. We will also analyze the regulation of large chromosomal segments (BACs) carrying groups of ADH genes to detect potential interactions in a chromosomal context. We hypothesize that inter-individual differences in regulatory sequences cause differences in ADH gene expression. We will identify and characterize polymorphisms in the regulatory regions and test their effects on gene expression in vitro. These two aims will be closely coupled, with the localization of cis-acting elements directing our search for polymorphisms, and our detection of functional polymorphisms helping to prioritize further study of the cis-acting elements.These studies will contribute to our understanding of the genetic factors underlying differences among individuals in the metabolic, pharmacological and pathological effects of alcohol consumption. They will also increase our basic understanding of gene regulation.